Exlar Electric Test and Simulation Actuator Systems

Delivering more accurate and trouble-free test actuators. Exlar Electric Test and Simulation Actuator Systems

Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com entertainment simulators, Exlar actutors are Paradigm Shift ergonomic endurance directly controlled in Mechanical test equipment, geo- by the system’s logical test equipment, electric servo Testing System wear testing, and even amplifi er. No Technology aircraft structural testing intermediary such and dynamic simulation. as oil or air is required to create Historically, manufacturers and motion. System users of mechanical test ap- The Benefi ts compliance result- paratus and motion simulators ing from use of have accepted the inaccuracies, of All-Electric fl uid power is a inconvenience and high mainte- Test Actuator major contributor nance costs of hydraulic actua- to inaccuracy of tion. However, today’s simula- Systems tors and test stands are often hydraulic actua- Exlar’s patented roller used in environments where tor systems. The screw linear actuator contamination from oil leaks is higher stiffness of technology allows users to not permissable and greater ac- a planetary perform the analysis and testing curacy is required. Exlar offers roller screw-based actuator pro- needed to verify products’ de- a full range of all-electric test vides greater system response actuators and position controls signs without the high cost of in- and stability assuring precise which provide the dynamic per- stallation, constant maintenance, and crisp control, and stiffness formance and long life required environmental issues, and en- is not stroke-sensitive. for test and simulation equip- ergy consumption encountered ment. with servo hydraulic systems. Speed, Load Ratings and Lifetime Improved Control Exlar actuator systems due Exlar actuators allow designers to their design can operate at of motion simulators and test speeds of of 40 inches per sec- systems to experience a sub- ond which is substantially faster stantial improvement in than conventional servo hydrau- control over that lic systems. achieved using hydraulic Load ratings and lifetime for systems. all-electric systems compete handily with hydraulic systems, providing equivalent, and oftentimes greater performance. Given that an all-electric system requires very minimal maintenance, the load and life factor Fifteen years become distinct advantages experience in the design, over an hydraulic option. manufacture and implementa- tion of planetary roller screw actuators gives Exlar the edge in applying all-electric actuation for use in applications ranging from motion bases, hexapods,

2 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com Reduced Service and Six Degree- Reduced Risk of of-Freedom Specimen Damage Maintenance Motion System control characteris- Exlar electric actuators Hexapod tics are maintained without eliminate the service and adjustment or tuning, over maintenance cost of complex widely varying environmental and contaminant-sensitive conditions, as calibration does hydraulic systems. This not depend on temperature savings combined with and contamination sensitive less installed cost means hydraulic valves and fl uid minimal ongoing mediums. Exlar actuators also expense. maintain a safe position upon the application or removal of Energy Savings power, thus reducing the risk With today’s cost of of inadvertent damage to test energy, power con- specimens. sumption is an important factor in Much Less Infrastructure choosing which technology is em- Exlar systems require only AC ployed. Exlar’s electromechanical No moving of plumbing, hoses, power with easy connection solutions are 80% energy effi cient and accumulators, no recali- of cables between the servo compared to 50% or less for fl uid bration, no bleeding of hydrau- amplifi er and the actuator. power actuation. This increased lic lines, and no clean-up is No hydraulic power supplies, effi ciency means lower long-term required. System operation is lines, water cooling or associ- cost. all digital eliminating drift and ated facilities are required, allowing continuous storage often reducing initial cost to a Reduced Set-up and and recall of set-up and cali- fraction of the cost of a hy- Reconfi guration Time bration parameters. draulic system Exlar’s servo actuators are con- nectorized in the most convenient Quiet Operation Space Savings manner allowing connection and Electric actuation is very quiet The space consumed by test disconnection with the simple twist compared to fl uid power system components can be of a connector. Once programmed, actuators. The noise level of critical to the design of the electric systems generally operate hydraulic actuators (not test cell as well as the space with little or no additional calibra- including the hydraulic power constraints of the facility. tion for the duration of its use. supply) can reach levels Because an electro- Simply un- of 85 decibels or more. Exlar mechanical system plug cables actuators operate at eliminates the need by hand (no high rates of speed and yet for the hydraulic tools re- maintain decibel levels in power module and quired) and the low 70’s. system piping, the position the overall area taken up actuator in by the system can be the new greatly reduced. This location and space savings can be reconnect to a key in providing an begin opera- effective and attractive tion. test or simulation system without the expense of adding or modifying your existing facility.

3 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com research and creativity is a revo- on industrial equipment The Challenge lutionary design which incorpor- ranging from carpet weaving ates a high performance machines and machine tools, to For years, industry has sought brushless servo motor with a simulation and test equipment out a clean and effi cient all- novel mechanism for converting and submarines. All actuators electric alternative to hydrau- the motor’s power and speed to portray the unique characteristics lic and pneumatic cylinders. highly accurate and reliable linear of producing the power density, The promise of such a device motion. speed and robustness of hy- would be the elimination of the draulic and pneumatic actuation environmental issues associ- The Result — Since delivering without the inconvenience and ated with hydraulic fl uids, the the fi rst actuator to the world’s operating expense of fl uid power. noise and inconsistency of leading liquid packaging com- pneumatics, and a dramatic pany in 1993, the company has reduction in power consump- supplied over 10,000 units of tion. Today, process engineers this elegant but simple device are facing increasing demands for producing precise, yet highly for more accurate and better robust linear robust linear mo- responding position control. Epoxy-coated tion. Exlar’s inverted roller screw These trends are driven by actuators are being used today Aluminum Housing regulatory controls for cleanli- ness and effi ciency combined with the market’s demand for more accurate control of their processes. Engineers have Threaded Rollers universally agreed that the solution for addressing both Preloaded Angular these needs lies in an an all- electric actuator. The chal- Contact Bearings lenge has been to build such a device which delivers the promises of electric actuation, yet maintains the robustness and moderate cost of fl uid Chrome Plated power actuators. Extending Rod The Design — To meet this challenge, Exlar embarked on a mission to create a new kind of electrical actuator. Tradi- tional ball and acme screws were rejected due to their lack of robustness and limited service life when used in continuous motion applications. Direct acting electric actuators were found to be prohibitively expensive, energy ineffi cient, Sealed Output Rod and lacking the stability and stiffness needed to ensure ac- curacy. The result of Exlar’s

4 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com all-electric actuator which is The Solution extremely compact, yet de- The Operation -- Exlar’s patented livers similar performance linear actuator is based on a to a hydraulic cylinder in unique design for integrating a terms of force, robustness robust and efﬁ cient threaded roller to shock and long service mechanism into the interior of a life. high power density, high performance brushless servo motor. In response to current ﬂ ow, This combination results in an the servo motor produces torque and power in rota- tion. The internal roller screw mechanism converts MS Style Connectors Std. the rotational motion and torque to a high force, high speed linear output to act on the the applied load. Construction includes a series of load-bearing,

threaded rollers assembled The greater number of in a planetary arrangement. contact points in a roller This assembly provides the mechanical screw compared to a ball interface between screw (above) gives roller the threaded inside screws a longer life, higher surface of the hollow load capacity and greater (rotating) cylinder and stiffness. the threaded surface of the (force-generating) extending rod. The threaded surfaces of the rollers are of a matched helix conﬁ guration and precision machined to contact the rotating Position cylinder and follower at many Feedback points concurrently. The large number of mechanical inter- faces (typically in excess of 100) Inside Threaded Cylinder combine with their shape to create a total contact surface area much greater than that found in Neodymium Iron a comparable sized ball screw Boron Magnets mechanism. This unique design provides dynamic life and shock Integral 3 Phase DC resistance which is typically 15 Brushless Servo Motor with times greater than ballscrew T-LAMTM Stator mechanisms with similar dimen- sions.

5 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com accurate feedback of position, ac- Wave Simulation Successful celeration and velocity information, The high force capabilty and static and with optional integral load cells, control combined with an oil-free Applications can also offer very accurate feed- environment makes the Exlar back of true loading. system a perfect choice for wave in Test and genera- Simulation tion Aircraft Structural Testing appli- Exlar actuators are ideal for use in cations. aircraft structural dynamic testing Exlar as well actuators as are avail- satellite able in and strokes up to eight feet in length, space can provide 80 inch per second vehicle velocity, and 40,000 pound force. testing. Case material is aluminum with Entertainment/Animatronics Exlar actuators and controls do epoxy paint and options include The compact packages offered not cross couple or operate in an various grades of stainless steel. in the Exlar product line make for uncontroller manner during power Sealing is standard IP54 or IP65. perfect animatronic solutions. Ex- up, shutdown or emergency stop cellent controllability and high force conditions. They are available density have made Exlar the with locking, back driving and an Clean Room preferred choice internal brake (activated on power Exlar actuators are ideal for clean for some of the fail). This avoids the need for room or even vacuum chambers, world’s largest sophisticated load abort manifolds in semiconductors and biomedi- theme parks and and complex shutdown electronics cal as they do not use hydraulic movie studios. and greatly reduces the risk of an fl uid and can even be operated errant system operation resulting in without lubricants. a damaged specimen. Road Simulation Road simulators for automobiles, motorcycles, trucks and SUVs re- Hazardous Environments quire an actuator that not only For lab safety, Exlar electric atua- provides tors can be built for work in a haz- aggressive ardous environment. Testing that motion involves fuel, hot exhaust, and capabilities engine and high opera- Strength Testing thrust tion The small package size, high loads, but will ben- force density, high rigidity and the also offers long life, little mainte- efi t from ability to offer equal compressive nance and precise data feedback. actua- and tensile force output make Exlar’s electro-mechanical actuators Exlar tors provide all of these features that do Actuators eliminating the common problems not ideal for with hydraulic systems such as require a fl ammable hydraulic fl uid. incorpora- in consistent force and position Furthermore, Exlar actuators can tion into control, cumbersome set up, and be provided with a Class I, Div 1 strength diffi cult tuning and temperature explosion proof rating. testing compen-sation. The high stiffness equipment. High actuator rigidity of Exlar’s actuators provide offers the machine builder

6 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com the ease of set up and tuning Small Size Actuators Wear/Life Testing not available when dealing with Exlar actuators do not have Exlar actuators are well suited to compressible hydraulic fl uid. break-out friction issues or oil act as wear and life testing de- Position and force measure- column vices for components or equip ments are attainable with ease instabili- ment. Exlar from the electro-mechanical ties, actuators system offering fl exible data even are currently in gathering solutions. for the use performing smallest life testing of Man Rated Simulators actuator. automotive Often brake systems, Simulators designed for use by used in earth moving people have a unique set of re- injection equipment quirements well suited to using molding machines for plastic parts, controls and Exlar’s all you get the same control stability even life testing of ball screws! electro-mecha- and fi delity whether you’re using The long life of the Exlar actua- ical servo two inch frame or unique sizes. tor’s planetary roller screw fi lls the actuators. The application requirements of life obvious benefi t testing applications even at high is the elimina Quality Assurance Testing loads and high cycle rates. tion of oil in sys Exlar actuators provide verifi cation tems that are that production parts are meeting often used their rated specifi cations. Several Wind Tunnel indoors in envi- E-Test Actuators are currently in MTS Systems Corporation utilizes ronments that can not tolerate oil use by one Exlar’s GSX60 actuators as the leaks. Hydraulic systems gener- of the world’s legs of an ally have stored energy in the largest inverted six- form of column compliance and manufacturers degree-of sometimes nitrogen charged ac- of thrust freedom cumulators. Hydraulic actuators bearings hexapod. can also create decelerations far verifying the These hexa- beyond the acceptable range for static load ratings of their bearings pods manipulate the position of human use when the payload in production. 50% and 60% scale Formula 1 is stopped rapidly by an errant models in wind tunnels for the re- valve closure. Flight Simulation search and development purpos- Leading simulator manufacturers es of the race car design teams. Mechanical like Flight Safety International and The systems require the Assembly Test L3 rely on Exlar actuators precise control of roll, ing with Load to provide smooth pitch and heave within Feedback and realistic controls the wind tunnel to Exlar actuators resistance for their provide the accura- are used to test fl ight and vehicle cy and repeatability steering wheel simulators. The of positioning that assemblies. The smoothness of Exlar’s the designers actuators com- oller screw actuators require. The form press two splined parts held apart and T-Lam motor tech- factor, precise by an internal spring. Every test nology, combined with control, and high cycle includes a force measure- robust designs, 100% rigidity of the Exlar ment made by a load cell embed- duty cycle capability, and GSX60 actuators provide ded in the actuator (standard long life make Exlar the perfect MTS Systems Corp with the option) to determine if the part choice for electro-mechanical linear motion solution that they meets the specifi ed motion/force simulation solutions. require for this demanding appli- profi le. cation. 7 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com data normally required during test Exlar Features operation. The system accepts GSX Series both analog and digital com- and Options mands. Analog is either 0-10V Compact or 4-20 mA and can be set up to Provide control position, velocity or force. ElectricTest Multiple forms of position feed-

Complete back are available including Actuators Alternative to incremental and absolute encod- With form factors similar to ers, resolvers, LVDT or magne- hydraulic cylinders, Exlar’s Servo torestrictive linear sensors. An linear actuators provide a integral force sensor can provide compact, integrated Hydraulic Test accurate real-time force measure- motor and actuator ment while motion is generated. in frame sizes from 2 inches Systems The same servo amplifi er used (50mm) to 18 inches for Exlar’s (200mm) and force linear ac- outputs of 580 pounds (2570 N) tuators can to 40,000 pounds (200kN). Exlar be used actuators are ideal when used with Exlar’s in applications where cyclic fre- rotary quency up to 10 Hz and strokes actuators. are from 0.1 to 10 feet. Exlar’s All options linear actuators are dimensionally are avail- similar to fl uid power actuators able with with standard NFPA front and rear Exlar rotary clevis mounts which allow, in many actuators applications, direct substitution for with the exception of magnetor- Exlar’s technology is unmatched existing equipment. estrictive LVDT position feedback by any other electro-mechanical and integrated load cell. Exlar Standard mounting confi gurations device due to its patented inte- amplifi ers can be interchanged include trunnion and face and grated roller screw actuator. easily as requirements vary from fl ange mounts, rear clevis, foot and Additional features such as inte- test to test. side mounts. Custom mounts con- gral linear position and force fi gured to meet your exact needs sensors provide test engineers can be designed and built. with reliable, dynamic data. Precise feedback of key operat- GSX Series Specifi cations ing parameters assure precise Nominal Max. Rated Max. L10 Life control and event recording. Frame Stroke Force Speed at Rated Size Size Available Lbf (N) in/sec Load Closed-Loop Electric in (mm) in (mm) (mm/sec) in x 106 Actuator Servo System (mm x 106) Exlar in most cases offers a 2 12 578 33 228.6 GSX20 complete system which includes (50) (300) (2571) (.8k) (5806) actuators, amplifi ers, and cables. 3 18 1347 25 508 GSX30 This allows the user to procure (75) (450) (5992) (.6k) (12903) electronics that are designed 4 18 3966 37.5 76.2 GSX40 specifi cally for use in testing ap- (100) (450) (17642) (.9k) (1935) plications and operate together. 5 18 8544 40 38.1 Systems are fully engineered to GSX50 (130) (450) (38006 (1k) (968) provide optimized performance, 7 12 12389 40 57.15 trouble-free long life and the GSX60 (180) (250) (55109) (1k) (1452)

8 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com FT Series Ft Series force tube actuators use a planetary roller screw mounted Long Stroke inside a telescoping tube mechanism. The follower is attached to Actuators the moveable force tube, which then extends and retracts as the The FT Series actuators are screw rotates. suited to operate where longer strokes and higher thrusts are required. The FT Series product Exlar’s Front and Rear offering consists Clevis Mount GSX Series of a roller screw Actuator thrust unit and a conventional NEMA or metric frame motor sized Standard Features to deliver the force and speed • Linear speed range to 25 needed to accomplish the ap- in/sec (635 mm/sec) plication. • Force rating range to 12,389 Options pounds/force (55,109N) FT Series Features • Stainless Steel • Stroke length range 3 -18 • Stroke lengths up to 8 feet • Special Mountings inches (75 - 450 mm) (150 mm to 2.5 m) • Vacuum • Typical life exceeding hun- • Force rating up to 20,000 lbs • Dust Free dreds of millions of (88,964 N) continuous, 40,000 • Oil or Air Cooling full-stroke operations lbs (177,929 N) peak • Uninteruptable Power • Backlash < .004 in (.1mm) • Speed range up to 60 in/sec • IP65 sealing • IP65 rating (1,524 mm/sec) • Multiple motor mounting op- Custom Actuation Optional Features tions Exlar specializes in custom • Planetary roller screw drive • Handwheel actuators where certain materi- • Long life and high load • Incremental or absolute rotary als and features are incorporated capacity feedback which meet the exact speciﬁ ca- • Shock resistance • LVDT or magnetorestrictive tion of unique testing or simula-

linear sensors tion applications. • Embedded force sensor • Air or liquid cooling FT Series Speciﬁ cations • Special output shaft and mounting Frame Gear Maximum Max. Cont Peak Maximum Size Motor Stroke Force Force Speed • Preloaded zero backlash Size in (optional) in lbf lbf in/sec • Stainless steel housing (mm) (mm) (kN) (kN) (mm/sec) 3.5 48 2000 4000 60 FT35 SLG060 (89) (1219) (8.9) (17.8) (1524) 6.0 96 10000 20000 39 FT60 SLG090 (152) (2438) (45.4) (90.8) (991) 8.0 96 20000 40000 35 FT80 SLG115 (203) (2438) (90.8) (178) (889)

9 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com while the motor is rotary test stands where actua- Exlar SLG powered. tor size and efﬁ ciency is Additionally critical. In shaft driven Series Rotary optimum loads, Exlar’s rotary control actuators are Actuators and directly coupled shaft-to-shaft. Rotary actuators are also provided This by Exlar, which, in most cases eliminates offer an ideal solution for the ungainly testing and simulation mechanisms applications usually necessary to convert the linear motion of pneumatic and hydraulic cylinders to rotational motion.

Standard Features • Output speed range from 0.01 reliability to1,250 rpm are achieved • Torque range to 2900 lbf-in due to the mech- (328 Nm) anical design of • Compact size this motor. Since electric • Expected life of hundreds of millions of cycles that require an servo motors operate more • IP65 sealing applied torque, rather effi ciently at moderate velocities than an applied linear force. rather than low speeds, the plane- Exlar’s rotary actuators include tary gear reducer allows the actua- Optional Features a high power density, electrically tor to operate at effi ciencies • Handwheel operated brushless servo motor typically greater than 80%. Three • Incremental or absolute rotary closely coupled to a high strength different sizes of rotary actuators feedback planetary gear reduction mecha- allow the test system designer to • Stainless steel housing nism. This acts to multiply the match the right actuator with each • Explosion proof Class I, div 1, output load capacity of the motor specifi c application encountered. Group B, C and D and to assure rigidity in position Exlar’s closed-loop, servo con- • Custom shaft and mounting trolled rotary actuators are ideal for

SLG Series Speciﬁ cations Nominal Frame Max. Output Torque Maximum Output Speed Size Size in (mm) lbf (Nm) Backlash (rpm) SLG060 2 (50) 340 (38) 10 arc min 1250 SLG090 3 (75) 1550 (175) 10 arc min 1000 SLG115 4 (100) 2900 (328) 10 arc min 750

10 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com 4-20 mA output SV Series which repre- sents the actual Digital position of the actuator on a Positioner real time basis. Exlar’s SV Series Four sizes of Positioner was the SV Series designed for use Positioner allow with Exlar rotary and you to effi - linear actuators in test ciently match and simulation the desired SV Series Specifi cations systems. The setup force and velo- Analog Inputs and operation is ity (frequency) Position Command or Sen- tailored to make its performance sor Signal: 12 bit (4096 incre- operation functional needed in your ments) over range of 4-20mA, 0 and easy to use with application. to 10 VDC or +10 VDC a 0 to 10, -10 to +10, Absolute Feedback: 12 bit or 4-20 mA analog SV Control (4096 increments) over range of position, velocity or Features 0-5 VDC force (torque) • Linear or Auxilliary: Set Point Con- command signal. The rotary actuator trol, 12 bit (4096 increments) amplifi er then generates control over 0 to 10 or + 10 VDC the pulse width modulted electric • Position control proportional to power for the actuator to pro- analog or digital commands (Mod- Analog Output duce the motion in accordance bus) Current Position: 12 bit with your command signal. The • Analog or digital output (4096 increments) over 0-20mA system is completely closed proportional to actual position loop to assure replication of the • 24 Volt digital inputs and outputs Digital Inputs: Enable opera- intended motion. It also al- • ASCII or Modbus protocol serial tion, Go/To Emergency Position, lows optimization of the control communication Fault Reset, Home Limit, Home through the proper setting of the • Auxiliary analog control capability Initiate, Motor Thermal Switch. loop gains and amplitude. Optional Features Digital Outputs: Programmable The SV2000 provides an analog • Absolute positioning (with optional Warnings, Fault output in the form of 0-10 Volt or absolute sensor) Output Rating Serial Port: RS485 Standard; RS232 with Converter Box Current (available from Exlar) ASCII and RMS Peak Power Voltage In Modbus protocol. Amps Amps Watts VDC VAC 8 15 2 kW -- 71-240, 3 phase Resolution of Control: 12 bit SV2008 7 15 2 kW 100-350 71-240, 1 phase (4096 increments) per motor SV2008-24 8 15 2 kW 20-50 -- revolution times the pitch of lead (turns of the lead per inch 15 30 2.5 kW 100-350 71-240, 3 phase SV2015 of increment) for linear actuators 7 30 2.5 kW -- 71-240, 1 phase or times the gear reduction ratio SV2015-24 15 30 2.5 kW 20-50 -- for rotary motion. 35 70 6 kW 100-350 71-240, 3 phase SV2035 20 70 6 kW -- 71-240, 1 phase Environmental Rating: NEMA 1 SV4008 10 15 3 kW 250-760 180-540 3 phase only SV4020 20 30 7 kW 250-760 180-540 3 phase only SV4050 50 50 18 kW 250-760 180-540 3 phase only 11 Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com The Company -- Headquartered in suburban Minneapolis, Minnesota, Exlar serves a global customer base with an extensive standard product line and complete engineering support for custom actuator applications.

Exlar supports a large network of sales representatives in North America. To ﬁ nd your local dealer, visit our website at www.exlar.com or call our headquar- ters at 952-500-6200.

18400 West 77th Street Chanhassen, MN 55317 952-500-6200 Toll Free 855-620-6200 Fax 952-368-4877

Courtesy of Steven Engineering, Inc. - 230 Ryan Way, South San Francisco, CA 94080-5370 - Main Office: (650) 588-9200 - Outside Local Area: (800) 258-9200 - www.stevenengineering.com